How exactly is Twitter the exact same thing as RSS? I don't really see how someone tweeting about a new blog post being the same as what RSS does in any way other than being notified that a blog post has been written and possibly a title. I agree it is pubsub but that's pretty shaky. If the implication is that because we have Twitter then we do not need RSS .. I just think that's sort of ridiculous; is 140 characters the end of the road now? If not then Twitter is not a great solution to replace RSS. You can argue that RSS feeds have become like unread email but I think that is a different issue.